It depends- - - -are you cranking a brand new engine with normal compression pressure and correct clearances, or a worn out piece of junk? Either way, a good condition 550 battery should be sufficient. In extremely cold or hot situations, I'd want to boost the CCA a little higher.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!